Stem Leydig cells: Current research and future prospects of regenerative medicine of male reproductive health.

Stem cells are specialized cells that can renew themselves through cell division and can differentiate into multi-lineage cells. Mesenchymal stem cells are adult stem cells that exist in animal and human tissues. Mesenchymal stem cells have the ability to differentiate into mesodermal lineages, such as Leydig cells, adipocytes, osteocytes, and chondrocytes. Mesenchymal stem cells express cell surface markers, such as cluster of differentiation (CD) 29, CD44, CD73, CD90, CD105, and lack the expression of CD14, CD34, CD45 and HLA (human leukocyte antigen)-DR. Stem Leydig cells are one kind of mesenchymal stem cells, which are present in the interstitial compartment of testis. Stem Leydig cells are multipotent and can differentiate into Leydig cells, adipocytes, osteocytes, and chondrocytes. Stem Leydig cells have been isolated from rodent and human testes. Stem Leydig cells may have potential therapeutic values in several clinical applications, such as the treatment of male hypogonadism and infertility. In this review, we focus on the latest research on stem Leydig cells of both rodents and human, the expression of cell surface markers, culture, differentiation potential, and their applications.

Differential effects of sleep deprivation on behavior and microglia in a brain-region-specific manner in young and aged male mice.

Microglia, resident immune cells in the central nervous system, constantly monitor the state of the surrounding brain activity. The animal model induced by sleep deprivation (SD) is widely used to study the pathophysiological mechanisms of insomnia and bipolar disorder. However, it remains unclear whether SD affects behaviors in young and aged male mice and microglia in various brain regions. In this study, we confirmed brain region-specific changes in microglial density and morphology in the accumbens nucleus (Acb), amygdala (AMY), cerebellum (Cb), corpus callosum (cc), caudate putamen, hippocampus (HIP), hypothalamus (HYP), medial prefrontal cortex (mPFC), and thalamus (TH) of young mice. In addition, the density of microglia in old mice was higher than that in young mice. Compared with young mice, old mice showed a markedly increased microglial size, decreased total length of microglial processes, and decreased maximum length. Importantly, we found that 48-h SD decreased microglial density and morphology in old mice, whereas SD increased microglial density and morphology in most observed brain regions in young mice. SD-induced hyperactivity was observed only in young mice but not in old mice. Moreover, microglial density (HIP, AMY, mPFC, CPu) was significantly positively correlated with behaviors in SD- and vehicle-treated young mice. Contrarily, negative correlations were shown between the microglial density (cc, Cb, TH, HYP, Acb, AMY) and behaviors in vehicle-treated young and old mice. These results suggest that SD dysregulates the homeostatic state of microglia in a region- and age-dependent manner. Microglia may be involved in regulating age-related behavioral responses to SD.

Observation of the possible magnetic correction above the Curie temperature in Cr2Si2Te6 single crystals.

Intrinsic magnetic semiconductors hold great promise in the fields of fundamental magnetization and spintronics. One such semiconductor is Cr2Si2Ti6 (CST), a quasi two-dimensional (2D) magnetic semiconductor with potential applications in future magnetic devices. However, the origin of ferromagnetism in CST remains a mystery. To investigate this, ac/dc susceptibility and electronic spin resonance (ESR) measurements were conducted. Based on ac susceptibility scaling, the critical temperature (TC) for the ferromagnetic (FM) to paramagnetic (PM) phase transition was found to be ∼32.5 K, with a critical exponent of δ = 6.7 from the critical isotherm, ß + γ = 1.72 from the temperature dependence of the crossover line, and γ = 1.43 from the temperature dependence of susceptibility along the same line. All critical exponents were found to be consistent with the dc magnetization scaling method. However, above and below TC, the origin of magnetism cannot be explained by a single theory. To explore the origin of abnormal magnetic critical behavior, ESR measurements were performed. Below T* ∼ 130 K, the ESR measurements revealed that the resonance field width (ΔH) tends to increase and decrease for the applied magnetic field H parallel and perpendicular to the c axis, respectively, indicating the onset of magnetic interaction even in the PM state. Meanwhile, the deviation from Curie-Weiss behavior below T* also confirmed the occurrence of magnetic correlation above the TC in CST. These observations suggest that the competition and cooperation among the direct and indirect interactions, the structural distortion and the van der Waals interaction at high temperature should be considered to investigate the origin of anomalous magnetism in CST. The present results provide valuable insights into the nature of ferromagnetism in 2D magnetic semiconductors.

Erythrocyte ENT1-AMPD3 Axis is an Essential Purinergic Hypoxia Sensor and Energy Regulator Combating CKD in a Mouse Model.

SIGNIFICANCE STATEMENT: Hypoxia drives kidney damage and progression of CKD. Although erythrocytes respond rapidly to hypoxia, their role and the specific molecules sensing and responding to hypoxia in CKD remain unclear. In this study, we demonstrated in a mouse model that erythrocyte ENT1-AMPD3 is a master energy regulator of the intracellular purinergic hypoxic compensatory response that promotes rapid energy supply from extracellular adenosine, eAMPK-dependent metabolic reprogramming, and O 2 delivery, which combat renal hypoxia and progression of CKD. ENT1-AMPD3-AMPK-BPGM comprise a group of circulating erythroid-specific biomarkers, providing early diagnostic and novel therapeutic targets for CKD. BACKGROUND: Hypoxia drives kidney damage and progression of CKD. Although erythrocytes respond rapidly to hypoxia, their role and the specific molecules sensing and responding to hypoxia in CKD remain unclear. METHODS: Mice with an erythrocyte-specific deficiency in equilibrative nucleoside transporter 1 ( eEnt1-/- ) and a global deficiency in AMP deaminase 3 ( Ampd3-/- ) were generated to define their function in two independent CKD models, including angiotensin II (Ang II) infusion and unilateral ureteral obstruction (UUO). Unbiased metabolomics, isotopic adenosine flux, and various biochemical and cell culture analyses coupled with genetic studies were performed. Translational studies in patients with CKD and cultured human erythrocytes examined the role of ENT1 and AMPD3 in erythrocyte function and metabolism. RESULTS: eEnt1-/- mice display severe renal hypoxia, kidney damage, and fibrosis in both CKD models. The loss of eENT1-mediated adenosine uptake reduces intracellular AMP and thus abolishes the activation of AMPK α and bisphosphoglycerate mutase (BPGM). This results in reduced 2,3-bisphosphoglycerate and glutathione, leading to overwhelming oxidative stress in eEnt1-/- mice. Excess reactive oxygen species (ROS) activates AMPD3, resulting in metabolic reprogramming and reduced O 2 delivery, leading to severe renal hypoxia in eEnt1-/- mice. By contrast, genetic ablation of AMPD3 preserves the erythrocyte adenine nucleotide pool, inducing AMPK-BPGM activation, O 2 delivery, and antioxidative stress capacity, which protect against Ang II-induced renal hypoxia, damage, and CKD progression. Translational studies recapitulated the findings in mice. CONCLUSION: eENT1-AMPD3, two highly enriched erythrocyte purinergic components that sense hypoxia, promote eAMPK-BPGM-dependent metabolic reprogramming, O 2 delivery, energy supply, and antioxidative stress capacity, which mitigates renal hypoxia and CKD progression.

Perfluorotetradecanoic acid exposure to adult male rats stimulates corticosterone biosynthesis but inhibits aldosterone production.

Perfluorotetradecanoic acid (PFTeDA) is a novel perfluoroalkyl substance that ubiquitously exists in the environment. However, whether PFTeDA affects adrenal cortex function remains unclear. Male Sprague-Dawley rats (age of 60 days) were daily administered with PFTeDA (0, 1, 5, and 10 mg/kg body weight) through gavage for 28 days. PFTeDA did not change body and adrenal gland weights. PFTeDA markedly elevated serum corticosterone level at 10 mg/kg but lowering serum aldosterone level at this dosage without influencing serum adrenocorticotropic hormone level. PFTeDA thickened zona fasciculata without affecting zona glomerulosa. PFTeDA remarkably upregulated the expression of corticosterone biosynthetic genes (Mc2r, Scarb1, Star, Cyp21, Cyp11b1, and Hsd11b1) and their proteins, whereas downregulating aldosterone biosynthetic enzyme Cyp11b2 and its protein, thereby distinctly altering their serum levels. PFTeDA markedly downregulated the expression of antioxidant genes (Sod1 and Sod2) and their proteins at 10 mg/kg. PFTeDA significantly decreased SIRT1/PGC1α and AMPK signaling while stimulating AKT1/mTOR signaling. Corticosterone significantly inhibited testosterone production by adult Leydig cells at >0.1 µM in vitro; however aldosterone significantly stimulated testosterone production at 0.1 nM. In conclusion, exposure to PFTeDA at male rat adulthood causes corticosterone excess and aldosterone deficiency via SIRT1/PGC1α, AMPK, and AKT1/mTOR signals, which in turn additively leads to testosterone deficiency.

Halogenated bisphenol A derivatives potently inhibit human and rat 11ß-hydroxysteroid dehydrogenase 1: Structure-activity relationship and molecular docking.

Chlorinated bisphenol A (BPA) derivatives are formed during chlorination process of drinking water, whereas bisphenol S (BPS) and brominated BPA and BPS (TBBPA and TBBPS) were synthesized for many industrial uses such as fire retardants. However, the effect of halogenated BPA and BPS derivatives on glucocorticoid metabolizing enzyme 11ß-hydroxysteroid dehydrogenase 1 (11ß-HSD1) remains unclear. The inhibitory effects of 6 BPA derivatives in the inhibition of human and rat 11ß-HSD1 were investigated. The potencies for inhibition on human 11ß-HSD1 were TBBPA (IC50, 3.87 µM) = monochloro BPA (MCBPA, 4.08 µM) = trichloro BPA (TrCBPA, 4.41 µM) > tetrachloro BPA (TCBPA, 9.75 µM) > TBBPS (>100 µM) = BPS (>100 µM), and those for rat 11ß-HSD1 were TrCBPA (IC50, 2.76 µM) = MCBPA (3.75 µM) > TBBPA (39.58 µM) > TCBPA = TBBPS = BPS. All these BPA derivatives are mixed/competitive inhibitors of both human and rat enzymes. Molecular docking studies predict that MCBPA, TrCBPA, TCBPA, and TBBPA all bind to the active site of human 11ß-HSD1, forming hydrogen bonds with catalytic residue Ser170 except TCBPA. Regression of the lowest binding energy with IC50 values revealed a significant inverse linear regression. In conclusion, halogenated BPA derivatives are mostly potent inhibitors of human and rat 11ß-HSD1, and there is structure-dependent inhibition.

Highly N-Doped Fe/Co Phosphide Superstructures for Efficient Water Splitting.

Developing an inexpensive bifunctional electrocatalyst for overall water splitting is critical for acquiring scalable green hydrogen and thereby realizing carbon neutralization. Herein, an "all-in-one" method is developed for the fabrication of highly N-doped binary FeCo-phosphides (N-FeCoP) with hierarchical superstructure, this delicately designed synthesis route allows the following merits for benefiting water splitting electrocatalysis in alkaline, including high N/defect-doping for mediating the surface property of the as-made N-FeCoP, binary Fe and Co components exhibiting strong coupling interaction, and 3D hierarchical superstructure for shortening diffusion length and thereby improving reaction kinetics. Electrochemical measurements reveal that the N-FeCoP sample exhibits very low overpotentials for initiating the hydrogen and oxygen evolution reactions. Remarkably, overall water splitting can be promoted on N-FeCoP using a commercial primary Zn-MnO2 battery. The developed synthesis strategy may potentially inspire the preparation of other N-doped metal-based nanostructures for broad electrocatalysis.

Dynamic changes in microglia in the mouse hippocampus during administration and withdrawal of the CSF1R inhibitor PLX3397.

Pexidartinib (PLX3397), a colony-stimulating factor-1 receptor (CSF1R) inhibitor, is currently in phase 1-3 clinical trials as a treatment for a variety of tumours. CSF1R signalling regulates the development, survival and maintenance of microglia, the resident brain innate immune cells. In this study, we examined the effects of PLX3397 in the drinking water of mice on microglia in the hippocampus using ionized calcium-binding adapter molecule 1 (Iba1, a microglial marker) immunocytochemistry. A high concentration of PLX3397 (1 mg/mL) significantly decreased the density of Iba1-immunoreactive cells after 7 days of exposure, but a low concentration of PLX3397 (0.5 mg/mL) did not. In addition, both low and high concentrations of PLX3397 significantly increased the intersection number, total length and maximum length of microglial processes in male mice. PLX3397 administered for 21 days eliminated microglia with 78% efficiency in males and 84% efficiency in females. Significant increases in microglial processes were found after both seven and 21 days of PLX3397 exposure in males, whereas decreases in microglial processes were observed after both 14 and 21 days of exposure in females. After PLX3397 withdrawal following its administration for 14 days in males, the soma size quickly returned to normal levels within a week. However, the microglial density, intersection number and total length of microglial processes after 3 days of recovery stabilized to untreated levels. In summary, these findings provide detailed insight into the dynamic changes in microglial number and morphology in the hippocampus in a dose- and time-dependent manner after PLX3397 treatment and withdrawal.

Glucagon-like peptide-1 promotes Leydig cell regeneration from stem cells in rats.

In brief: Glucagon-like peptide-1 stimulates stem Leydig cell development. Glucagon-like peptide-1 stimulates stem Leydig cell differentiation without affecting its proliferation. Abstract: The regulators of stem Leydig cell (SLC) development remain largely unknown. The effect of glucagon-like peptide-1 (GLP-1) on rat SLC proliferation and differentiation was investigated using a 3D tissue culture system and an ethane dimethane sulfonate (EDS)-treated in vivo LC regeneration model. RNA-seq analysis was performed to analyze pathways in which GLP-1 may be involved. GLP-1 (3 and 30 nmol/L) significantly increased medium testosterone abundances and upregulated the expression of Scarb1, Cyp11a1, and Hsd11b1. GLP-1 in vitro did not affect SLC proliferation by 5-Ethynyl-2'- deoxyuridine (EdU) incorporation assay. Intratesticular injection of GLP-1 (10 and 100 ng/testis) into the LC-depleted testis from day 14 to day 28 post-EDS significantly increased serum testosterone abundances and upregulated the expression of Cyp11a1, Hsd3b1, and Hsd11b1. It did not affect the number of HSD11B1+ and CYP11A1+ LCs. RNA-seq analysis revealed that GLP-1 upregulated several pathways, including cAMP-PKA-EPAC1 and MEK/ERK1/2. GLP-1 stimulates SLC differentiation without affecting its proliferation, showing its novel action and mechanism on rat SLC development.

Association of demographics, cardiovascular indicators and disability characteristics with 7-year coronary heart disease incident in persons with disabilities.

OBJECTIVE: Previous studies had demonstrated that disability increases mortality in patients with coronary heart disease (CHD). However, for people who had been disabled but do not have baseline cardiovascular disease, there is still limited data on how they might develop CHD. This study aimed to investigate the incidence and predictors of CHD in people with disabilities. METHODS: We conducted a 7-year retrospective study utilizing data from the Shanghai Comprehensive Information Platform for Persons with Disabilities Rehabilitation. Subjects aged over 18 years with at least four annual complete electronic health records were included. The primary outcome was CHD, defined as ischemic heart disease or myocardial infarction. Kaplan-Meier analysis and log-rank tests were used to compare cumulative CHD for sub-populations, stratified by age, gender, and the classification of disabilities. Cox regression was used to identify the potentially important factors. RESULTS: Out of 6419 persons with disabilities, 688 CHD cases (mean age 52.95 ± 7.17 years, male 52.2%) were identified, with a cumulative incidence of 10.72% and an incidence density of 15.15/1000 person-years. The incidence density of CHD is higher in the male gender, people over 45 years, and those with physical disabilities. Male (HR = 1.294, 95% CI, 1.111-1.506), hypertension (HR = 1.683, 95% CI, 1.405-2.009), diabetes mellitus (HR = 1.488, 95% CI, 1.140-1.934), total cholesterol (HR = 1.110, 95% CI, 1.023-1.204), and physical disabilities (HR = 1.122, 95% CI, 1.019-1.414) were independently associated with CHD. CONCLUSION: The findings indicate that the incidence of CHD differs across disability categories rather than the severity of disability. People with physical disabilities had significantly higher risks for the development of CHD. The underlying physiological and pathological factors need to be further studied.

Prevalence and associated risk factors for chronic kidney disease in the elderly physically disabled population in Shanghai, China: a cross-sectional study.

BACKGROUND: The global prevalence of chronic kidney disease (CKD) in the general population is relatively clear. Our previous study showed that elderly individuals who are physically disabled are more likely to experience kidney function impairment, and the main purpose of this study was to determine the prevalence and risk factors associated with CKD in elderly patients with physical disabilities. METHODS: A total of 2679 elderly individuals with physical disabilities from the 2018 Shanghai Disability Health Survey were screened to calculate the prevalence of CKD. Multiple logistic regression was performed to identify the factors associated with CKD. Detailed subgroup analyses of disability level were also conducted. RESULTS: We confirmed CKD in 287 of 2679 (10.7%) participants. Female sex, age, history of hypertension, red blood cell count, albumin, urea, and uric acid (UA) were independently correlated with CKD. Age and UA abnormalities were common risk factors for different levels of disabilities. CONCLUSION: The prevalence of CKD is higher in the mild level of older physically handicapped individuals. Age and the level of UA should also be considered in this population. The preventive strategies for patients with two levels of elderly disability should have different focuses.

Curcumin analogues exert potent inhibition on human and rat gonadal 3ß-hydroxysteroid dehydrogenases as potential therapeutic agents: structure-activity relationship and in silico docking.

Curcuminoids are functional food additives, and the effect on gonadal hormone biosynthesis remains unclear. Gonads contain 3ß-hydroxysteroid dehydrogenase isoforms, h3ß-HSD2 (humans) and r3ß-HSD1 (rats), which catalyse pregnenolone into progesterone. The potency and mechanisms of curcuminoids to inhibit 3ß-HSD activity were explored. The inhibitory potency was bisdemethoxycurcumin (IC50, 1.68 µM) >demethoxycurcumin (3.27 µM) > curcumin (13.87 µM) > tetrahydrocurcumin (109.0 µM) > dihydrocurcumin and octahydrocurcumin on KGN cell h3ß-HSD2, while that was bisdemethoxycurcumin (1.22 µM) >demethoxycurcumin (2.18 µM) > curcumin (4.12 µM) > tetrahydrocurcumin (102.61 µM) > dihydrocurcumin and octahydrocurcumin on testicular r3ß-HSD1. All curcuminoids inhibited progesterone secretion by KGN cells under basal and forskolin-stimulated conditions at >10 µM. Docking analysis showed that curcuminoids bind steroid-active site with mixed or competitive mode. In conclusion, curcuminoids inhibit gonadal 3ß-HSD activity and de-methoxylation of curcumin increases inhibitory potency and metabolism of curcumin by saturation of carbon chain losses inhibitory potency.

Distinct inhibitory strength of bisphenol A analogues on human and rat 11ß-hydroxysteroid dehydrogenase 1: 3D quantitative structure-activity relationship and in silico molecular docking analysis.

Bisphenol A (BPA) analogues are developed to replace BPA usage. However, their effects on 11ß-hydroxysteroid dehydrogenase 1 (11ß-HSD1) are largely unknown. The inhibitory effects of BPA and 10 BPA analogues with the substituents on the bridge moiety on human and rat 11ß-HSD1 were explored in human and rat liver microsomes. The strength of inhibiting human 11ß-HSD1 was bisphenol FL (IC50, 3.87 µM) > bisphenol Z (6.86 µM) > bisphenol AF (9.42 µM) > bisphenol C (16.14 µM) > bisphenol AP (32.14 µM) = bisphenol B (32.34 µM) > 4,4'-thiodiphenol (67.35 µM) > BPA (297.35 µM) > other BPA analogues (ineffective at 100 µM). The strength of inhibiting rat 11ß-HSD1 was bisphenol Z (IC50, 14.44 µM) > 4,4'-thiodiphenol (19.01 µM) > bisphenol B (20.13 µM) > bisphenol F (22.10 µM) > bisphenol E (33.04 µM) > bisphenol AF (49.67 µM) > bisphenol C > (56.97 µM) > bisphenol AP (62.71 µM) >bisphenol FL (96.31 µM) > other BPA analogues (ineffective at 100 µM). Bisphenol A, AF, AP, B, C, F, FL, Z, and 4,4'-thiodiphenol bind to the active sites of human and rat 11ß-HSD1. Regression of LogP and molecular weight with IC50 values revealed distinct inhibitory pattern (negative correlation for human 11ß-HSD1 vs. positive correlation for rat enzyme). Regression of the lowest binding energy with IC50 values revealed a significant positive regression. 3D QSAR pharmacophore analysis showed one hydrogen bond acceptor and two hydrogen bond donors for human 11ß-HSD1. In conclusion, most BPA analogues are more potent inhibitors of human and rat 11ß-HSD1 enzymes and there is structure-dependent and species-dependent inhibition.

Citrinin inhibits the function of Leydig cells in male rats in prepuberty.

Citrinin, a mycotoxin existing in fruits, has nephrotoxicity, hepatotoxicity and embryotoxicity. The effects of citrinin on Leydig cell development in prepuberty remains unclear. Male Sprague-Dawley rats were gavaged with 0, 1, 2.5, and 5 mg/kg citrinin from postnatal days 21-28. Citrinin at 5 mg/kg significantly decreased serum testosterone levels, while increasing serum LH and FSH levels. Citrinin at 1-5 mg/kg markedly downregulated Hsd17b3 and HSD17B3 expression, while upregulating Srd5a1 (SRD5A1) and Akr1c14 (AKR1C14) expression at 2.5 and/or 5 mg/kg. Citrinin at 5 mg/kg also significantly increased PCNA-labeling index in Leydig cells. Citrinin at 5 mg/kg significantly raised testicular MDA amount, whiling at 2.5 and 5 mg/kg downregulating SOD1 and SOD2 expression. Citrinin at 5 mg/kg markedly decreased the ratio of Bcl2 to Bax, in consistent with the increased apoptosis in Leydig cells judged by TUNEL assay. Enzymatic assay revealed that citrinin inhibited rat testicular HSD3B1 activity at 100 µM and HSD17B3 activity at 10-100 µM. Citrinin at 50 µM and higher also induced reactive oxygen species (ROS) and apoptosis of R2C cell line. In conclusion, citrinin inhibits Leydig cell development at multiple levels via different mechanisms and oxidative stress partially plays a role.

Direct inhibition of bisphenols on human and rat 11ß-hydroxysteroid dehydrogenase 2: Structure-activity relationship and docking analysis.

Bisphenols (BPs) as endocrine-disrupting compounds have drawn attention to their health hazards. Whether a BP interferes with glucocorticoid metabolism remains unclear. 11ß-Hydroxysteroid dehydrogenase 2 (11ß-HSD2) is a key glucocorticoid-metabolizing enzyme that controls fetal glucocorticoid levels across the placental barrier and mineralocorticoid receptor specificity in the kidney. In this study, 11 BPs were tested to inhibit human placental and rat renal 11ß-HSD2 and were analyzed for inhibitory potency, mode action, and docking parameters. BPs had inhibitory potency against human 11ß-HSD2: BPFL>BPAP>BPZ>BPB>BPC>BPAF>BPA>TDP and the IC10 values were 0.21, 0.55, 1.04, 2.04, 2.43, 2.57, 14.43, and 22.18 µM, respectively. All BPs are mixed inhibitors except BPAP, which is a competitive inhibitor for human 11ß-HSD2. Some BPs also inhibited rat renal 11ß-HSD2, with BPB (IC50, 27.74 ± 0.95) > BPZ (42.14 ± 0.59) > BPAF (54.87 ± 1.73) > BPA (77.32 ± 1.20) > other BPs (about 100 µM). Docking analysis showed that all BPs bound to the steroid-binding site, interacting with the catalytic residue Tyr232 of both enzymes and the most potent human 11ß-HSD2 inhibitor BPFL acts possibly due to its large fluorene ring that has hydrophobic interaction with residues Glu172 and Val270 and π-stacking interaction with catalytic residue Tyr232. The increase in the size of substituted alkanes and halogenated groups in the methane moiety of the bridge of BPs increases its inhibitory potency. Regressions of the lowest binding energy with inhibition constant indicated that there was an inverse regression. These results indicated that BPs significantly inhibited human and rat 11ß-HSD2 activity and that there were species-dependent differences.

Benzene ring bisphenol A substitutes potently inhibit human, rat, and mouse gonadal 3ß-hydroxysteroid dehydrogenases: Structure-activity relationship and in silico docking analysis.

Bisphenol A (BPA) is a chemical used in the production of certain plastics and resins. Recent research has found that BPA can inhibit the activity of 3ß-hydroxysteroid dehydrogenase/Δ5,4-isomerases (3ß-HSDs). Whether benzene ring BPA substitutes can inhibit human, rat, and mouse gonadal 3ß-HSDs, the structure-activity relationship and the underlying mechanism remain unclear. In this study, we compared 6 benzene ring BPA substitutes to BPA in the inhibition of human, rat, and mouse gonadal 3ß-HSDs and conducted structure-activity relationship and in silico docking analysis. The inhibitory activity (IC50) of human 3ß-HSD2 in KGN cells ranged from about 0.02 µM for bisphenol H to 8.75 µM for BPA, that of rat 3ß-HSD1 in testicular microsomes ranged from 0.099 µM for bisphenol H to 31.32 µM for BPA, and that of mouse 3ß-HSD6 ranged from 0.021 µM for BPH to ineffectiveness for 100 µM BPA. These compounds acted as mixed inhibitors with LogP inversely correlated with IC50 and ΔG positively correlated with IC50 value. Docking analysis showed that these compounds bind to the steroid active site of the 3ß-HSD enzymes. In conclusion, some benzene ring BPA substitutes potently inhibit gonadal 3ß-HSD in various species, and lipophilicity and binding affinity determine their inhibitory strength.

Exposure to 4-nonylphenol compromises Leydig cell development in pubertal male mice.

Exposure to 4-nonyl phenol (4-NP) on Leydig cell (LC) development and function remains poorly understood. We explored the effects of 4-NP on LC development and elucidate the underlying mechanisms. Male (28-day-old) mice received orally 4-NP (0.125, 0.25, and 0.5 mg/kg/day) for 28 days. We found that 4-NP at ≥ 0.125 mg/kg markedly compromised serum testosterone levels and LC numbers. Gene and protein expression analysis demonstrated downregulation of key genes and their proteins involved in LC steroidogenesis, including Star, Cyp11a1, Cyp17a1, Hsd17b3, Hsd3b6, and Scarb1. Furthermore, exposure to 4-NP induced oxidative stress, as evidenced by elevated reactive oxygen species (ROS) and malondialdehyde (MDA), as well as reduced superoxide dismutase 1/2 and catalase (CAT). Apoptosis was also observed in LCs following exposure to 4-NP, as shown by an increased BAX/BCL2 ratio and caspase-3. A TM3 mouse LC line further confirmed that 4-NP induced ROS and the expression of apoptosis-related genes and proteins. In conclusion, this study demonstrates that 4-NP exposure compromises LC development through multiple mechanisms.

Bisphenol S stimulates Leydig cell proliferation but inhibits differentiation in pubertal male rats through multiple mechanisms.

Bisphenol S (BPS) is a novel bisphenol A (BPA) analogue, a ubiquitous environmental pollutant that disrupts male reproductive system. Whether BPS affects Leydig cell maturation in male puberty remains unclear. Male Sprague-Dawley rats (age of 35 days) were daily gavaged to 0, 1, 10, 100, and 200 mg/kg/day from postnatal days 35-56. BPS at 1-10 mg/kg/day and higher doses markedly reduced serum testosterone and progesterone levels but it at 200 mg/kg/day significantly increased estradiol level. BPS at 100 and 200 mg/kg/day significantly elevated serum luteinizing hormone (LH) levels. BPS at 1-10 mg/kg/day and higher doses significantly reduced inhibin A and inhibin B levels. BPS at 100 and 200 mg/kg/day markedly increased CYP11A1+ Leydig cell number, but did not affect HSD11B1+ (a mature Leydig cell marker) cell number. BPS at 10 mg/kg/day and higher doses significantly downregulated the expression of Cyp11a1 and at 100 and 200 mg/kg/d significantly lowered Cyp17a1, Hsd11b1, and Nr5a1 in the testes. BPS at 100 and/or 200 mg/kg/day significantly elevated Lhb in the pituitary. BPS at 100 and 200 mg/kg/day significantly increased the phosphorylation of AKT1, AKT2, and CREB without affecting total AKT1, AKT2, and CREB levels. BPS at 1-100 µM significantly suppressed testosterone production and induced proliferation of primary immature Leydig cells after 24 h of treatment and these actions were reversed by estrogen receptor α antagonist, ICI 182780, and partially reversed by vitamin E. BPS at 0.1-10 µM significantly increased oxidative stress of Leydig cells in vitro. BPS also directly inhibited 17ß-hydroxysteroid dehydrogenase 3 activity at 10-100 µM. In conclusion, BPS causes hypergonadotropic androgen deficiency in male rats during pubertal exposure via activating ESR1 and inducing ROS in immature Leydig cells and directly inhibiting 17ß-hydroxysteroid dehydrogenase 3 activity.

Bisphenol A Analogues Inhibit Human and Rat 11ß-Hydroxysteroid Dehydrogenase 1 Depending on Its Lipophilicity.

Bisphenol A (BPA) analogues substituted on the benzene ring are widely used in a variety of industrial and consumer materials. However, their effects on the glucocorticoid-metabolizing enzyme 11ß-hydroxysteroid dehydrogenase 1 (11ß-HSD1) remain unclear. The inhibitory effects of 6 BPA analogues on the inhibition of human and rat 11ß-HSD1 were investigated. The potencies of inhibition on human 11ß-HSD1 were bisphenol H (IC50, 0.75 µM) > bisphenol G (IC50, 5.06 µM) > diallyl bisphenol A (IC50, 13.36 µM) > dimethyl bisphenol A (IC50, 30.18 µM) > bisphenol A dimethyl ether (IC50, 33.08 µM) > tetramethyl bisphenol A (>100 µM). The inhibitory strength of these chemicals on rat 11ß-HSD1 was much weaker than that on the human enzyme, ranging from 74.22 to 205.7 µM. All BPA analogues are mixed/competitive inhibitors of both human and rat enzymes. Molecular docking studies predict that bisphenol H and bisphenol G both bind to the active site of human 11ß-HSD1, forming a hydrogen bond with catalytic residue Ser170. The bivariate correlation of IC50 values with LogP (lipophilicity), molecular weight, heavy atoms, and molecular volume revealed a significant inverse regression and the correlation of IC50 values with ΔG (low binding energy) revealed a positive regression. In conclusion, the lipophilicity, molecular weight, heavy atoms, molecular volume, and binding affinity of a BPA analogue determine the inhibitory strength of human and rat 11ß-HSD isoforms.

In utero di-(2-ethylhexyl) phthalate-induced testicular dysgenesis syndrome in male newborn rats is rescued by taxifolin through reducing oxidative stress.

Testicular dysgenesis syndrome in male neonates manifests as cryptorchidism and hypospadias, which can be mimicked by in utero phthalate exposure. However, the underlying phthalate mediated mechanism and therapeutic effects of taxifolin remain unclear. Di-(2-ethylhexyl) phthalate (DEHP) is the most abundantly used phthalate and can induce testicular dysgenesis syndrome in male rats. To explore the mechanism of DEHP mediated effects and develop a therapeutic drug, the natural phytomedicine taxifolin was used. Pregnant Sprague-Dawley female rats were daily gavaged with 750 mg/kg/d DEHP or 10 or 20 mg/kg/d taxifolin alone or in combination from gestational day 14 to 21, and male pup's fetal Leydig cell function, testicular MDA, and antioxidants were examined. DEHP significantly reduced serum testosterone levels of male pups, down-regulated the expression of SCARB1, CYP11A1, HSD3B1, HSD17B3, and INSL3, reduced the cell size of fetal Leydig cells, decreased the levels of antioxidant and related signals (SOD2 and CAT, SIRT1, and PGC1α), induced abnormal aggregation of fetal Leydig cells, and stimulated formation of multinucleated gonocytes and MDA levels. Taxifolin alone (10 and 20 mg/kg/d) did not affect these parameters. However, taxifolin significantly rescued DEHP-induced alterations. DEHP exposure in utero can induce testicular dysgenesis syndrome by altering the oxidative balance and SIRT1/PGC1α levels, and taxifolin is an ideal phytomedicine to prevent phthalate induced testicular dysgenesis syndrome.